Stripping apparatus as used in the production of cardboard and like blanks

ABSTRACT

The invention provides stripping apparatus for use in the manufacture of cardboard and similar blanks in which the cut blanks are passed through a roll pair, one of the rolls having pins or projections to engage with the scrap areas of the blank and deflect them out of the feed path, and in which each roll is encircled by a series of conveyor belts so that the belts serve to maintain the blank in the feed path, the belts being adjusted along the axes of the rolls so as to engage the blank only over the areas which are to be maintained in the feed path and not over the areas which are to be displaced out of the feed path as scrap; in a modification, some of the belts extend about the one roll and through the feed path, these additional belts being arranged so as to engage only with the scrap material and they thus serve to convey the scrap material out of the feed path.

United States Patent [19] Bishop Sept. 10, 1974 [75] Inventor: Thomas Desmond Bishop, Solihull,

England [73] Assignee: The Deritent Engineering Company Limited, Birmingham, England [22] Filed: July 7, 1972 [21] Appl. No.2 269,777

[30] Foreign Application Priority Data July 10, 1971 Great Britain 32476/71 [52] US. Cl. 93/36 A, 83/103 [51] Int. Cl B311) 1/00 [58] Field of Search 93/36 A; 83/103; 271/45 [56] References Cited UNITED STATES PATENTS 1,987,224 1/1935 Bergstern 93/36 A X 2,410,611 11/1946 Pratt et a1 3,524,364 8/1970 Bishop 93/36 A X Primary ExaminerAndrew R. Juhasz Assistant ExaminerLeon Gilden Attorney, Agent, or Firm-Marshall & Yeasting [5 7] ABSTRACT The invention provides stripping apparatus for use in the manufacture of cardboard and similar blanks in which the cut blanks are passed through a roll pair, one of the rolls having pins or projections to engage with the scrap areas of the blank and deflect them out of the feed path, and in which each roll is encircled by a series of conveyor belts so that the belts serve to maintain the blank in the feed path, the belts being adjusted along the axes of the rolls so as to engage the blank only over the areas which are to be maintained in the feed path and not over the areas which are to be displaced out of the feed path as scrap; in a modification, some of the belts extend about the one roll and through the feed path, these additional belts being arranged so as to engage only with the scrap material and they thus serve to convey the scrap material out of the feed path.

5 Claims, 5 Drawing Figures PATENTED SE91 0 I974 -SHEH 20F '3 Fig.4-

PAIENIED WI j 3.834.291

SHIEH 30E 3 STRIPPING APPARATUS AS USED IN THE PRODUCTION OF CARDBOARD AND LIKE BLANKS BACKGROUND OF THE INVENTION This invention relates to stripping apparatus as used in the production of cardboard and other blanks when a pattern of cuts is made in a blank, so as to define for example a base, side walls, a lid and flaps of a carton to be erected from the blank subsequently, and wherein the blank material not utilised in the said base or other areas (hereinafter called scrap) is separated from the remainder.

It is known for this purpose to feed the cut blank through a stripping apparatus comprising a pair of rollers, one of which may have a yielding surface and the other of which carries a pattern of projections such as pins or blocks so located and timed synchronously with blank movement as to register with the scrap areas, and displace them out of the plane of the blank so as to separate them therefrom, such apparatus being herein called of the kind referred to. Prior to such separation, the scrap is connected to the blank at spaced points, so as to prevent premature separation in the manufacturing cycle.

Such out blanks are relatively fragile even if made of thick board, and tend to deform, or follow the roll contour especially where the whole of the leading edge of the blank is a scrap piece. Various proposals have been made hitherto for facilitating feed of the blanks through the stripper but all are subject to some disadvantage or uncertainty. The objects of the invention are to provide improvements leading to efficient and reliable stripping.

SUMMARY OF THE INVENTION In accordance with the invention, apparatus of the kind referred to is characterised by the provision of a plurality of endless conveyor loops, encircling one of the rollers and the loops passing through the rollers nip so as to be adapted to feed blanks through the nip, the lateral spacing between the several loops permitting operation of the projections therebetween.

Preferably the loops are in pairs and the upper loops encircle the roller which carries the projections and these loops may be flat belts, whereas the lower loops are of circular or Vee cross-sectional shape, and encircle the other roll, so as to lie below the flat belts and be pressed into the yielding surface of the lower roll thereby: alternatively both (or all) loops may be of circular cross-sectional shape.

All of the loops may extend across header pulleys or wheels which maintain the loop shapes and lead the loops in converging relationship in feed into the rollers nip. The pulleys or like may be adjustable along their rotational axes to allow the loop positions to be adjusted to suit particular patterns of blanks.

The yielding surfaced roller may be of different diameter to the other roller, although geared together for the same peripheral speed, and the axes of the rollers may lie in parallel planes normal to the plane of the blanks in the feed path.

Where scrap material is to be removed from the lateral sides of the blank in the apparatus, addtional loops may be provided which generally encircle the upper roller in the same way as the previously mentioned loops, but which also extend downwardly through and below the feed path, so as to displace these lateral scrap portions out of the plane of feed.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagrammatic elevation showing the prior art arrangement.

FIG. 2 is a sectional elevation of apparatus in accordance with the invention, which may be compared with FIG. 1, and is taken on the line 2-2 of FIG. 3.

FIG. 3 is a sectional plan view of the apparatus, taken on the line of the feed path, that is on the line 3-3 of FIG. 2;

FIG. 4 is a transverse sectional view taken on the line 44 of FIG. 2, but showing the blank further advanced from the position illustrated in FIG. 3; and

FIG. 5 is a view similar to FIG. 2 but from one lateral side of the apparatus.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, all of which are some what diagrammatic, and in particular to FIG. 1, the conventional apparatus feed blanks l0, 11 through a series of treatment rolls such as those indicated by the reference 12, which serve to provide the pattern of cuts, creases and the like in the blanks 10, 11, and a separate pair of stripper rolls 14, 16 is provided, the lower of the pair being of smaller diameter than the upper one, being provided with a yielding surface layer 18, and being staggered slightly with respect to the upper roll 14. The upper roll is provided with apattem of pins 20, 22 which impinge upon the blank in the areas which are to be displaced out of the feed path so as to separate these areas of scrap material from the blank and displace them downwardly as is indicated by the reference 24 (FIG. 1) whilst the remainder of the blank is fed through the apparatus with the assistance of feed rolls, located in pairs before and after the roll pair 14, 16, these feed rolls being indicated by the reference numberals 26, 28.

Referring now to FIGS. 2 to 5 of the drawings, illustrating an embodiment of the present invention, and in particular to FIG. 2 thereof, it will be seen that a similar pair of stripping rolls 14, 16 is provided earring the pattern of pins 20, 22, in association with feed roll means 26, 28. Each of the rolls 14, 16 is generally encircled by a series of side by side, but laterally spaced along the axis of the roll, loops 32, 34 which extend parallel to one another through the nip between the rolls and on either side of the feed path, and are maintained in the loop formation by the feed rolls 26, 28 and by further loop formers 33, 36.

One typical blank is illustrated in FIG. 3 in a position in the nip, and comprises a blank area 40 surrounded by a generally peripheral frame of blank material which represents scrap, indicated by the reference numerals 42, 44, 46, 48.

The position of the loops 34 will be seen from FIG. 3, and it will be seen that these lie inwardly of the frame portions 42, 46 so that they extend under the required blank area 40 during progression of the blank along the feed path, and from FIG. 4 it will be seen that the loops 32 and the loops 34 co-operate together to grip the blank 40 therebetween. As previously mentioned, the lower loops 32 may be of circular or V cross-section so as to tend to embed in the yielding surface of the lower roll 16 (if such yielding surface is provided) and the upper loops 34 may be of relaively flat cross-section.

(Any desired number of pairs of such loops 32, 34 may be provided as may be required according to the complexities of the blanks being treated, and these are arranged along the roll axes so as to support and feed the blank and to lie on either side of the planes (which planes are normal to the axes of rotation of the rolls) contained by the projections or pins 20 and 22 during their rotational movement with the roll 14. Hence the loops do not interfere with the operation of the pins 20, 22 and permit the same to contact the scrap areas of the blank, but support the blank at lateral positions from the pins in the nip. The result is that scrap portions may be deflected out of the plane of the feed path by the pins whilst the remaining area of the blank, being the area, 40, is fed onwards in the feed path.

The positions of the loops along the length of the roll axes may be secured by the use of pulleys or the like on ones of the loop forming rolls and shafts 26, 28, 33, 36.

As best shown in FIG. 5, additional loops are provided at the lateral extremes of the rolls corresponding to the positions of the side scrap portions 42, 46 and which grip those side portions during the progress of the blank along the feed path. These additional loops 50, 50 extend around the same upper loop formers 26, 33, but around the axis of one of the lower loop formers 36 (but preferably around pulleys freely journalled on the shaft which supports the formers 36, since these loops 50 are travelling in the opposite direction to the loops 34 at that point).

As perhaps best illustrated in FIG. 4, the operation of the side loops 50 is to grip the lateral portions 42, 46 which are scrap areas from the original blank and deflect them downwards out of the feed path thus effecting positive separation from these scrap areas.

Desirably the blank is provided with cuts 52 to separate the areas 42 and 46 from the scrap areas 44 and 48, so that the areas 44 and 48 can be deflected separately by the pins as indicated in FIG. 4.

It will be appreciated that the roll 14 is to be driven in timed synchronism with the feed of the blanks, and enables rapid, efficient and thorough stripping of scrap areas to be performed.

I claim:

1. Stripping apparatus for use in the production of cardboard and other blanks to remove scrap areas from the blanks, comprising a backup roller having a substantially continuous peripheral surface, and a stripping roller carrying a pattern of projections to register with the scrap areas and displace them out of the plane of each blank, said rollers forming a nip through which the blanks are fed, wherein the improvement comprises a plurality of superimposed pairs of endless conveyor loops, the loops of each pair extending through said nip and also beyond said nip on both sides of said rollers, so as to guide a blank sandwiched between the loops and to prevent the blank from becoming deformed or wrapped around a roller, the pairs of loops being spaced apart to permit operation of the projections therebetween.

2. Stripping apparatus according to claim 1 including two additional loops, one encircling each end of the roller carrying said projections, a portion of each such additional loop being arranged to extend through and beyond the plane of the feed path defined by said pairs of conveyor loops to thereby deflect marginal scrap areas of the blanks out of the plane of the feed path.

3. Stripping apparatus as claimed in claim 1 wherein at least the conveyor loops which encircle the backup roller present narrow blank-engaging surfaces.

4. Stripping apparatus according to claim 3 wherein the conveyor loops which encircle the stripping roller present wide, flat blank-engaging surfaces.

5. Stripping apparatus according to claim 1 wherein the loops are mounted for lateral adjustment with respect to the direction of feed movement of the blanks. I 

1. Stripping apparatus for use in the production of cardboard and other blanks to remove scrap areas from the blanks, comprising a backup roller having a substantially continuous peripheral surface, and a stripping roller carrying a pattern of projections to register with the scrap areas and displace them out of the plane of each blank, said rollers forming a nip through which the blanks are fed, wherein the improvement comprises a plurality of superimposed pairs of endless conveyor loops, the loops of each pair extending through said nip and also beyond said nip on both sides of said rollers, so as to guide a blank sandwiched between the loops and to prevent the blank from becoming deformed or wrapped around a roller, the pairs of loops being spaced apart to permit operation of the projections therebetween.
 2. Stripping apparatus according to claim 1 including two additional loops, one encircling each end of the roller carrying said projections, a portion of each such additional loop being arranged to extend through and beyond the plane of the feed path defined by said pairs of conveyor loops to thereby deflect marginal scrap areas of the blanks out of the plane of the feed path.
 3. Stripping apparatus as claimed in claim 1 wherein at least the conveyor loops which encircle the backup roller present narrow blank-engaging surfaces.
 4. Stripping apparatus according to claim 3 wherein the conveyor loops which encircle the stripping roller present wide, flat blank-engaging surfaces.
 5. Stripping apparatus according to claim 1 wherein the loops are mounted for lateral adjustment with respect to the direction of feed movement of the blanks. 